Sitting at 20mm diameter and is 1.6mm thick it’s small but packs a punch with a nominal voltage output of 3V and a capacity of 90mAh. For other drain rates the capacity may be reduced, check the datasheet! Note that these are often “stacked” to make a 6V CR2032-sized pack of batteries.

Coming in at a 24.5mm diameter and 5mm thickness this battery kicks major butt with a nominal voltage of 3V and a capactiy of 610mAh! For other drain rates the capacity may be reduced, check the datasheet!